{"id":362,"date":"2018-02-03T23:20:47","date_gmt":"2018-02-03T22:20:47","guid":{"rendered":"http:\/\/astroriom.net\/wp1\/?p=362"},"modified":"2023-11-01T19:28:32","modified_gmt":"2023-11-01T18:28:32","slug":"les-planetes-et-leurs-observations","status":"publish","type":"post","link":"https:\/\/astroriom.net\/v2\/?p=362","title":{"rendered":"Les plan\u00e8tes et leurs observations"},"content":{"rendered":"\n<p><b>Il existe deux types de plan\u00e8tes&nbsp;:<\/b><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><span style=\"color: #a600a8;\"><u>Les telluriques<\/u><\/span> telles que Mercure (1) , V\u00e9nus (2) , la Terre (3) et Mars (4)&nbsp;; ce sont des plan\u00e8tes compos\u00e9es en grande partie de roches et de m\u00e9tal , leur surface est solide et leur densit\u00e9 relativement \u00e9lev\u00e9e. Elles ont peu de satellites, V\u00e9nus (<span style=\"font-size: small;\">faussement appel\u00e9e l\u2019\u00e9toile du berger) <\/span><span style=\"font-size: medium;\">et Mercure n\u2019en poss\u00e8dent pas<\/span>.<\/li>\n\n\n\n<li><span style=\"color: #a600a8;\"><u>Les gazeuses<\/u><\/span> <span style=\"color: #000000;\">telles que Jupiter (5) , Saturne (6) , Uranus (7) , Neptune (8)&nbsp;; ce sont des plan\u00e8tes en grande partie compos\u00e9es de gaz, essentiellement de l\u2019hydrog\u00e8ne et de l\u2019h\u00e9lium , elles poss\u00e8dent un noyau solide et sont entour\u00e9es d\u2019anneaux . Leur densit\u00e9 est faible, celle de Saturne est inf\u00e9rieure \u00e0 l\u2019eau .<\/span><\/li>\n<\/ul>\n\n\n\n<p><span style=\"color: #000000;\">D\u00e8s les temps les plus recul\u00e9s, les hommes ont constat\u00e9 que certains astres se d\u00e9pla\u00e7aient sur le fond du ciel \u00e9toil\u00e9&nbsp;; les Grecs les ont nomm\u00e9s <\/span><span style=\"color: #000000;\"><b>plan\u00e9ta<\/b><\/span><span style=\"color: #000000;\"> qui signifie \u00ab&nbsp;astre errant&nbsp;\u00bb , c\u2019est l\u2019origine du mot plan\u00e8te.<\/span><\/p>\n\n\n\n<p>Les six premi\u00e8res plan\u00e8tes (hormis la terre) sont facilement rep\u00e9rables dans le ciel \u00e0 l\u2019\u0153il nu , il suffit de consulter <b>les \u00e9ph\u00e9m\u00e9rides&nbsp;<\/b>: ce sont des tables qui situent les diff\u00e9rents \u00e9l\u00e9ments c\u00e9lestes .<\/p>\n\n\n\n<p>Elles sont visibles car elles sont proches du soleil et ainsi refl\u00e8tent sa lumi\u00e8re , contrairement aux \u00e9toiles qui fabriquent leurs particules de lumi\u00e8re que l\u2019on nomme photons .<\/p>\n\n\n\n<p>Avec un instrument, t\u00e9lescope ou lunette, l\u2019observation plan\u00e9taire prend une tout autre dimension&nbsp;: des nuances et certains d\u00e9tails de la surface sont visibles, les principaux satellites de Jupiter par exemple sont parfaitement discernables.<\/p>\n\n\n\n<p>Et pour en d\u00e9couvrir davantage, nous vous invitons \u00e0 venir rejoindre notre association &#8230;<\/p>\n\n\n\n<p>Ci-dessous la taille \u00e0 l\u2019\u00e9chelle des huit plan\u00e8tes du syst\u00e8me solaire ( les distances ne sont pas respect\u00e9es) .<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"632\" src=\"http:\/\/astroriom.net\/v2\/wp-content\/uploads\/2023\/11\/systeme-solaire-planetes-taille.jpg\" alt=\"\" class=\"wp-image-1136\" srcset=\"https:\/\/astroriom.net\/v2\/wp-content\/uploads\/2023\/11\/systeme-solaire-planetes-taille.jpg 1024w, https:\/\/astroriom.net\/v2\/wp-content\/uploads\/2023\/11\/systeme-solaire-planetes-taille-300x185.jpg 300w, https:\/\/astroriom.net\/v2\/wp-content\/uploads\/2023\/11\/systeme-solaire-planetes-taille-768x474.jpg 768w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Il existe deux types de plan\u00e8tes&nbsp;: D\u00e8s les temps les plus recul\u00e9s, les hommes ont constat\u00e9 que certains astres se d\u00e9pla\u00e7aient sur le fond du ciel \u00e9toil\u00e9&nbsp;; les Grecs les ont nomm\u00e9s plan\u00e9ta qui signifie \u00ab&nbsp;astre errant&nbsp;\u00bb , c\u2019est l\u2019origine du mot plan\u00e8te. Les six premi\u00e8res plan\u00e8tes (hormis la terre) sont facilement rep\u00e9rables dans le &hellip; <a href=\"https:\/\/astroriom.net\/v2\/?p=362\" class=\"more-link\">Lire la suite de <span class=\"screen-reader-text\">Les plan\u00e8tes et leurs observations<\/span><\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[28],"tags":[],"class_list":["post-362","post","type-post","status-publish","format-standard","hentry","category-planetes","no-featured-image"],"_links":{"self":[{"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/posts\/362","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=362"}],"version-history":[{"count":1,"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/posts\/362\/revisions"}],"predecessor-version":[{"id":1137,"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=\/wp\/v2\/posts\/362\/revisions\/1137"}],"wp:attachment":[{"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=362"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=362"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/astroriom.net\/v2\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=362"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}